A365423 - OEIS

A365423

Odd numbers k for which k and A163511(k) have the same prime signature.

3, 7, 31, 45, 55, 111, 119, 123, 127, 175, 207, 247, 253, 447, 567, 895, 927, 945, 957, 959, 987, 1005, 1007, 1017, 1503, 1519, 1887, 1919, 1983, 2013, 2023, 2031, 2037, 2045, 3325, 3567, 3835, 3839, 3927, 3965, 4015, 4025, 4029, 4031, 4063, 4085, 4087, 5887, 7035, 7095, 7119, 7163, 7167, 7679, 7791, 7839, 7917, 7931

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OFFSET

1,1

COMMENTS

See comments in A364297.

LINKS

Table of n, a(n) for n=1..58.

PROG

(PARI)

A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };

A163511(n) = if(!n, 1, my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));

A365421(n) = (A046523(A163511(n))==A046523(n));